The Animal Models Core will provide support to several projects in assessing in vivo strategies for gene therapy for cystic fibrosis (CF). The Gene Therapy Program at the University of Pennsylvania has extensive experience with the in vivo characterization of vectors in nonhuman primates and murine models. In the context of this P01, the Animal Models Core wilt assess vector efficacy and safety in cynomologus macaques as well as mice genetically deficient in CFTR. Novel AAV vectors based on new serotypes will emerge from Projects 1 and 2 and will be evaluated in nonhuman primates using reporter genes to assess efficiency and stability of gene expression as well as toxicity. These vector systems will also be developed for expression of CFTR and evaluated in the CFTR deficient mice. Vector preparations will be applied to the nasal epithelia which will be analyzed for electrophysiologic correction to the measurement of potential differences. Incorporated into these vectors will be constructs developed in Project 3 which reconstitute CFTR expression through 2 vectors via a mechanism of trans-splicing. The need for employing this approach is the limited packaging capacity of AAV which precludes the inclusion of a full CFTR minigene cassette. A similar series of experiments in nonhuman primates and CFTR deficient mice will be conducted utilizing promising new ientiviral pseudotypes that emerge from Project 4. It is anticipated that approximately 3 vector strategies will be studied in nonhuman primates each year of the grant, with 4 animals included in each group. In parallel, we estimate the analysis of approximately 10 vector strategies in the CFTR deficient mice each year.